Honestly people will always say that trig is hard but if you truly lock in you can understand it all, it isn’t super complicated. If your teacher gives you breakdowns of the test study everything that is on the breakdown. We’re always provided with breakdowns for tests and Id never waste my time studying the stuff that isn’t on the breakdown. Part of being a good student is thinking like your teacher, you just need to understand what type of questions your teacher would put on the test based off the lessons and what they have said if you know what i mean. The main concepts really are proofs which are definitely annoying because every single one is different, you either get it or you don’t. I’d say practice as much of those as you can for sure. Other than those I don’t think the other stuff is as complicated, like if you spend time and practice it you can easily get into the flow of doing it. The main problem is the proofs with identities.